adenosine triphosphate base pair biochemistry biopolymer biotechnology chemical bond dna dna polymerase dna sequencing edman degradation electronic music enzyme eukaryote frederick sanger genetic code genetics intron mass spectrometry monosaccharide music sequencer nucleotide oligosaccharide peptide mass fingerprinting polysaccharide primary structure protein protein sequencing pyrosequencing rna reverse transcriptase sequence motif structure determination wavelength